Sequence electronic combination lock

ABSTRACT

An electronic combination lock circuit which includes a source of direct current connected to the rotary pole of plural position switch. The pole connects the source to selected switch contacts in a predetermined sequence and order. The contacts are applied to combination of &#39;&#39;&#39;&#39;AND&#39;&#39;&#39;&#39; and bistable elements whereby the switch must first be set to a &#39;&#39;&#39;&#39;ready&#39;&#39;&#39;&#39; contact before the combination number which by selective action controls the direction of rotation. In the event the switch is rotated past the combination number, the bistable elements are reset and the lock memory is wiped clean. Thus after the first combination number is dialed, the direction of rotation reversed, and the next combination number dialed subsequent to the second &#39;&#39;&#39;&#39;ready&#39;&#39;&#39;&#39; number and again, if passed, the memory is reset. This is repeated for all the combination numbers after which the source is applied so as to a utilization network or to operate a release, alarm, or other output component. It is clear that other variations can be included as for example, having to pass a combination number more than once before proceeding to the next term.

United States Patent 1 June 27, 1972 Krueger [54] SEQUENCE ELECTRONIC COMBINATION LOCK [72] lnventor: Paul C. Krueger, 20 Wabash Ave., Wharton, NJ. 07885 [22] Filed: May 14, 1971 [21] Appl. No.: 143,379

[52] U.S.C1 ..317/l34 I51] lnt.Cl ..E05b49/00 [58] F1eldoiSearch.... ..3l7/l34 [56] References Cited UNITED STATES PATENTS 3,320,490 5/1967 Beck et a1 ..317/134 3,411,046 11/1968 Swannick ..317/l34 3,513,357 5/1970 Dittmore.. ...3l7/134 3,587,051 6/1971 Hovey ...3l7/l34 3,600,637 8/1971 Bergkuist.. ..317/134 ABSTRACT An electronic combination lock circuit which includes a source of direct current connected to the rotary pole of plural position switch. The pole connects the source to selected switch contacts in a predetermined sequence and order. The contacts are applied to combination of AND" and bistable elements whereby the switch must first be set to a ready" contact before the combination number which by selective action controls the direction of rotation. In the event the switch is rotated past the combination number, the bistable elements are reset and the lock memory is wiped clean. Thus after the first combination number is dialed, the direction of rotation reversed, and the next combination number dialed subsequent to the second ready number and again, if passed, the memory is reset. This is repeated for all the combination numbers after which the source is applied so as to a utilization network or to operate a release, alarm, or other output component. It is clear that other variations can be included as for example, having to pass a combination number more than once before proceeding to the next term.

9 Claims, 2 Drawing Figures PA'TENTEnJunz'i I972 SHEET 2 OF 2 FIG. 2

)NVENTOR PAUL C. KRUEGER SEQUENCE ELECTRONIC COMBINATION LOCK The invention described herein may be manufactured, used and licensed by or for the Government for governmental purposes without the payment to me of any royalty thereon.

BACKGROUND OF THE INVENTION The present invention relates to a locking system and more particularly pertains to an electronic combination lock circuit wherein the combination are dialed on a single-pole plural position switch thereby controlling the interconnected logic circuitry.

In the field of locks and other securing mechanisms, it has been the general practice to employ mechanical devices to perform such functions. In most situations such devices have proved reasonably satisfactory, but under certain conditions their use has been impractical and so magnetic and/or electric circuits have been substituted. Certain inherent limitations of these latter devices have restricted their use which include as in the case of magnetic or wired keys the relative ease with which they may be duplicated and picked" by acoustic sensors. Mechanical locks work poorly under extreme environmental conditions as, cold temperatures where icing can occur, especially where a number of moving parts are involved. The present invention overcomes these difficulties.

SUMMARY OF THE INVENTION The general purpose of this invention is to provide an electronic combination lock that has all the advantages of similarly employed prior art devices and has none of the above described disadvantages. To attain this, the present invention provides a unique combination of logic elements having inputs connected serially together and to selected contacts of a rotary switch whose pole, in turn, is connected to a direct our rent source. Sequential proper dialing of the rotary switch results in the logic circuits operating in much the same fashion as a shift register except that the final output stage energizes a utilization or a release mechanism. 2

I An object of the present invention is to provide a simple, inexpensive and relatively fool-proof sequential type electronic combination lock.

Another object is the provision of an electronic combination lock which duplicates the operation. of a mechanical lock but does not employ'any moving parts, operates under extreme'environment conditions, and preventsacoustic monitoring and picking. I

Still another object is to provide a combination lock which may be controlled or operatedfrom a remote location.

Other objects and many of the attendant advantages of this invention will be readily'appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

FIG. 1 is a block diagram of an embodiment made in accordance with the principle of this invention; and,

FIG. 2 is a block diagram of another embodiment of the invention.

DESCRIPTION OF A PREFERRED EMBODIMENT In the illustrated embodiment of FIG. I, the fixed terminal of pole II of a multiple contact rotary switch 12 is connected to one terminal 13 of an electrical source, such as battery 14. The multiple fixed contacts 15 of this switch are consecutively designated by numerals 0 through 9 (combination numbers) although more or less contacts could equally well have been employed. For illustrative purposes, the first combination number N has been selected as contact 9 while its ready" number has been chosen as contact 8, which is connected to one input 16 of a logic memory storage device 17 that is capable of assuming either of two stable states and may be a bistable element such as a flip-flop. The flip-flop (FF) is provided with a pair of input terminals l6, l8 and a pair of output terminals 19 and 20. Input 18 constitutes a reset and wherein a change of input on 16 or 18 will reverse the bistable condition of both output terminals such that where the inputs are initially set at 0" zero and output terminal 19 is at 0" zero while 20 is at 1" (outputs always of opposite state) an input from contact 8 which cause FF 17 to reverse its output states to provide a l at 19. The output terminal 19 is connected to input 21 of logic AND" circuit 22 and whose output terminal 23 is applied to input 24 of FF 25. The 1" signal transferred from the F F 17 AND gate 22 merely enables the gate but, does not provide any output. The first combination number 9 is then dialed and it is clear that by selecting a ready number (such as 8) which is disposed counterclockwise of its associated combination number, the requirement that a clockwise rotation is initially necessary is thereby imposed. With pole 11 set at contact 9 anoutput is applied to the other input 26 of gate 22 which then applies a 1" to input 24 of FF 25 and causes output terminal 27 to change state to a 1" condition. This output is transferred to both input 28 of tri-input reset AND gate 29 and input 30 of AND gate 31 which enables each gate 31 and gate 29 since terminal 32 of FF 33 is initially at 1". With the first combination number dialed the system must now be constrained to insure reversal of the direction of rotation for the next combination number N,(4). For this purpose, the contact of the next succeeding number 10 (after the first combination number 9 in the direction of initial rotation), is connected to input 34 of clear function or reset AND gate 29 which has already been enabled by l s" at its inputs 28 and 35. The l output of gate 29 is applied via connection 36 to the reset inputs 18, 37-4] of FFs 17, 25, 33, 42-44 respectively which thereupon resets all the F-Fs to their initial states necessitating redialing.

Under the proper sequential dialing procedure the next combination number (4) must be dialed in a counterclockwise rotation of the pole and some clear" number is selected intermediate 9 and 4, as for example 7, so that a subsequent passing of the pole through number 10 will not result in reset. When the pole 11 temporarily contacts the 7 in its travel toward 9, then a 1" is placed at input 45 of AND gate 31 previously enabled and the output 46 thereof couples a l to input 47 of FF 33. This results in the outputs of FF 33 reversing, so that a 0" appears at terminal 32 which disables reset gate 29 at input 35 so that dialing a 10 will not affect it and places a l at the other output 48 which is applied to input 49 of AND gate 50 thereby enabling it while simultaneously disabling gate 29. When the number 4 contact is reached a l is applied thereby to the other output 51 of gate 50 thus providing a 1 output to input 52 of FF 42. This action switches output terminal 53 thereof to its l state which in turn is simultaneously coupled to input 54 of clear function or reset AND gate 55 which is thereby enabled due to having a 1 at input 56 from FF 43 output terminal 57 which is in its initial state. This "1 from FF 42 is also applied to input 58 of AND gate 59 and enables this gate. In the event the switch is improperly dialed thereafter so as to pass number 3 the output thereof is connected to reset AND gate 55 at input 60 so as to provide a reset signal at its output 61 and connection 36 thereby resetting all the FFs.

Since the direction of rotation for the next combination number must be counterclockwise and it is desired to require rotation past this number the ready number is selected a 2 and when the pole through 6 and 7 to the number 2 a l is placed at input 62 of AND gate 59 which in turn provides a l at input 63 of FF 43 whose outputs reverse with a 0" at 57 that disables reset gate 55 and a 1" at 64. This latter l signal is simultaneously applied to input 65 of reset AND gate 66 and input 67 of AND gate 68 enabling both of these gates. Rotation of the switch pole continues until the combination number 6 is reached, whereupon the signal is applied to input 69 of gate 68 which I output is coupled to input 70 of FF 44 which causes output terminal 71 to switch from a l to a zero. The direct line 72 from the gate 68 output connects to a utilization element 73 which in this case is a relay winding via one pole 74 of STDP push button switch 75 with the other pole 76 connected intermediate F-F output 71 and reset line 36. Thus, if the correct combination sequence has been dialed a will be placed on the reset line (no affect) and the utilization element will be energized thus releasing the lock" when the switch 75 is operated. In the alternative if the pole is rotated past 6 to 7 then a l is applied thereby to input 77 of previously enabled reset gate 66 whose output resets the F-- F's. Again, if the final combination number 6 is not contacted by the pole 11 of rotary switch 12 when pushbutton switch 75 is depressed, the I initially at output 71 of F-F 44 will cause the F-Fs to be reset via line 36.

In the embodiment of FIG. 2 the rotary switch 12 has its pole 11 connected to ground so that if connected to a logic member it will effectively apply a 0" thereto. Considering the same combination as the previously described embodiment the N,-1 ready number 8 is first dialed which then places a 0 at input 100(A) of multivibrator or flip-flop 101 which is made-up of a pair of cross coupled NAND gates 102, 103. Thus the dialing of the number 8 removes the l" at 100(A) and places a 0" at output 104(D) and input 105(B) of F-F 106 which enables it. The combination number 9 is now reached and a 0" is applied to input 107 of F-F 106 which results in a trigger of the F-F and a l at output 108 and at input 109 of NAND gate 110 which enables the same. In the event N,+ l or is incorrectly dialed a 0 is placed at input 111 of F-F 101 which reverses the condition of 104 and places all of the system back to its initial state.

By next dialing the ready number 7 in rotating toward N,(4) a 0" is applied to inverter 112 that then applies a "1 to the input 113 of enabled NAND 110 to cause it to feed a "0 to input 114 to F-F 115 which results in a 0" at 116 and at input 117 of F-F 118. Output terminal 119 provides the enabling signal at input 120 of NAND 121 when N,(4) is dialed and places a 0" at F-F 118 input 122. Should the N,--] number 3 be dialed then a 0 at 123 of F-F 115 cancels and returns the F-Fs. Subsequent dialing of 2 applies a 0 at inverter 24 which in turn places a 0. at input 125 of NAND 121 and a "0" at input 126 of F-F 127 thereby whose switched output at 128 is coupled to the input 129 of terminal F-F 130. Thereafter when the last number 6 is dialed prior to 7 its 0" input at 131 provides a l at output 132 that as previously described energizes the utilization network 133 via pushbutton switch 134. It being understood that the auxiliary power or energy sources for the logic members has not been illustrated for simplicity. It should also be observed that the ready numbers could also be N,-X, N x and N,,-X

It should be understood, of course, that the foregoing disclosure relates to only a preferred embodiment of the invention and that numerous modifications or alterations may be made therein without departing from the spirit and the scope of the invention as set forth in the appended claims.

I claim:

1. An electronic combination circuit for a lock or the like having a combination sequence of numerals designated N,, N and N comprising:

a source of electrical energy connected to a pole of a multiple contact rotary switch having said con- 7 tacts designated 1, 2...N,

an electrically activated utilization means,

a plurality of logic AND gates each having a pair of inputs and an output,

a plurality of bistable logic memory elements each having a pair of inputs and outputs capable of alternately assuming opposed output conditions which are changed by an input received at one of said inputs, one of said inputs being a reset input and the other an active input,

a series logic path including all of said logic members starting with the first of said bistable elements and having serially connected therein one output of said bistable element, one input of said AND gate, said output of said AND gate and said active input of the next succeeding bistable element and terminating said path with the last of said AND gates,

electrical means connecting,

said N,X, contact to the active input of said first bistable element,

said N, contact to the free input of the first of said AND gates,

a contact intermediate contacts N, and N, to the free input of the second series connected AND gate,

said N, contact to the free input of the third series connected AND gate,

another of said contacts to the free input of the fourth series connected AND gate,

said N, contact to the free input of the last series connected AND gate,

said output of said last AND gate to said utilization means,

whereby when said pole is rotated to sequentially contact said combination numeral contacts, said utilization means will be energized.

2. The combination circuit according to claim 1 further including:

a first reset AND gate having three inputs and an output, and having its first input connected to said one output of the second of said series connected bistable elements, its second input connected to the N, X, contact, and its third input connected to the other output of the third series connected bistable element and having its output connected to said reset input of all of said bistable elements.

3. The combination circuit according to claim 2 further including:

a second reset AND gate having three inputs and an output and having its first input connected to the one output of the fourth series connected bistable element, its second input connected to contact N,-X,, its third input connected to the other output of the fifth bistable element and having its output connected to said reset input of all of said bistable elements.

4. The combination circuit according to claim 3 further including:

a third reset AND gate having a pair of inputs and an output connected to said reset input of all of said bistable elements, and having one input connected to the one output of the fifth of said bistable elements and the other input connected to the N, X, contact.

5. The combination circuit according to claim 4 further including:

a terminal bistable element connected to receive the output of said last AND gate and having its output connected to said reset input of all of said bistable elements.

6. An electronic combination circuit for a lock or the like having a combination sequence of numerals designated N,, N,....N, comprising:

a source of electrical energy connected to,

a pole of a multiple contact rotary switch having N consecutively numerically designated contacts (1,2...N) where N 2N! an electrically activated utilization means,

2 N -l AND gates each having a pair of inputs and an output,

2N, -1 bistable logic memory elements each having a pair of inputs and outputs capable of alternately assuming opposed output conditions which are changed by an input received at the active input and a reset input,

a series logic path including all of said logic members starting with the first of said bistable elements and having serially connected therein one output of said bistable element, one input of said AND gate, said output of said AND gate and said active input of the next succeeding bistable element and terminating said path with the 2 N,1 AND gate,

electrical means connecting the N,1 contact to the active input of the first bistable element,

said N, contacts each connected to the free input of the respective (2N, 1)th AND gate,

said output of said 2 N, -1 AND gate connected to' said utilization means.

7 The circuit according to claim 6 further including N -l input connected to the one output of the last connected bistareset AND gates each having three inputs and an output and ble element and the other input connected to the last dialed having the first input connected to said one output of the H 1 Contact- 2N, th bistable element, the second input connected to the N circuit according to claim 8 flmhel includiflli I 1 Contact, the third input connected thc other output f the 5 a terminal bistable element connected to receive the output 2N, l bistable element and having its output connected to last colfnectedfiND 8 and 8 said reset input of all of said bi tabl elements, output connected to said reset input of all of said bistable 8. The circuit according to claim 7 further including an N, elementsreset AND gate having two inputs and an output with one 10 

1. An electronic combination circuit for a lock or the like having a combination sequence of numerals designated N1, N2 and N3 comprising: a source of electrical energy connected to a pole of a multiple contact rotary switch having said contacts designated 1, 2...N, an electrically activated utilization means, a plurality of logic AND gates each having a pair of inputs and an output, a plurality of bistable logic memory elements each having a pair of inputs and outputs capable of alternately assuming opposed output conditions which are changed by an input received at one of said inputs, one of said inputs being a reset input and the other an active input, a series logic path including all of said logic members starting with the first of said bistable elements and having serially connected therein one output of said bistable element, one input of said AND gate, said output of said AND gate and said active input of the next succeeding bistable element and terminating said path with the last of said AND gates, electrical means connecting, said N1- X1 contact to the active input of said first bistable element, said N1 contact to the free input of the first of said AND gates, a contact intermediate contacts N1 and N2 to the free input of the second series connected AND gate, said N2 contact to the free input of the third series connected AND gate, another of said contacts to the free input of the fourth series connected AND gate, said N3 contact to the free input of the last series connected AND gate, said output of said last AND gate to said utilization means, whereby when said pole is rotated to sequentially contact said combination numeral contacts, said utilization means will be energized.
 2. The combination circuit according to claim 1 further including: a first reset AND gate having three inputs and an output, and having its first input connected to said One output of the second of said series connected bistable elements, its second input connected to the N1 + X1 contact, and its third input connected to the other output of the third series connected bistable element and having its output connected to said reset input of all of said bistable elements.
 3. The combination circuit according to claim 2 further including: a second reset AND gate having three inputs and an output and having its first input connected to the one output of the fourth series connected bistable element, its second input connected to contact N2-X1, its third input connected to the other output of the fifth bistable element and having its output connected to said reset input of all of said bistable elements.
 4. The combination circuit according to claim 3 further including: a third reset AND gate having a pair of inputs and an output connected to said reset input of all of said bistable elements, and having one input connected to the one output of the fifth of said bistable elements and the other input connected to the N3 + X1 contact.
 5. The combination circuit according to claim 4 further including: a terminal bistable element connected to receive the output of said last AND gate and having its output connected to said reset input of all of said bistable elements.
 6. An electronic combination circuit for a lock or the like having a combination sequence of numerals designated N1, N2...NL comprising: a source of electrical energy connected to, a pole of a multiple contact rotary switch having N consecutively numerically designated contacts (1,2...N) where N 2NL, an electrically activated utilization means, 2 NL-1 AND gates each having a pair of inputs and an output, 2NL-1 bistable logic memory elements each having a pair of inputs and outputs capable of alternately assuming opposed output conditions which are changed by an input received at the active input and a reset input, a series logic path including all of said logic members starting with the first of said bistable elements and having serially connected therein one output of said bistable element, one input of said AND gate, said output of said AND gate and said active input of the next succeeding bistable element and terminating said path with the 2 NL-1 AND gate, electrical means connecting the N1-1 contact to the active input of the first bistable element, said NL contacts each connected to the free input of the respective (2NL-1)th AND gate, said output of said 2 NL-1 AND gate connected to said utilization means.
 7. The circuit according to claim 6 further including NL-1 reset AND gates each having three inputs and an output and having the first input connected to said one output of the 2NLth bistable element, the second input connected to the NL + or - 1 contact, the third input connected the other output of the 2NL + 1 bistable element and having its output connected to said reset input of all of said bistable elements.
 8. The circuit according to claim 7 further including an NL reset AND gate having two inputs and an output with one input connected to the one output of the last connected bistable element and the other input connected to the last dialed NL + 1 contact.
 9. The circuit according to claim 8 further including: a terminal bistable element connected to receive the output of said last serially connected AND gate and having its output connected to said reset input of all of said bistable elements. 